Feature: File Editor (#789)

* feat: Add file management feature

* feat: Add auto-save functionality to file editor

* fix: Replace HardDriveDownload icon with Save icon for consistency

* fix: Prevent recursive copy/move and improve shell injection prevention

* refactor: Extract editor settings form into separate component

libs/types/src/settings.ts

@@ -1005,6 +1005,16 @@ export interface GlobalSettings {
   /** Terminal font family (undefined = use default Menlo/Monaco) */
   terminalFontFamily?: string;
 
+  // File Editor Configuration
+  /** File editor font size in pixels (default: 13) */
+  editorFontSize?: number;
+  /** File editor font family CSS value (default: 'default' = use theme mono font) */
+  editorFontFamily?: string;
+  /** Enable auto-save for file editor (default: false) */
+  editorAutoSave?: boolean;
+  /** Auto-save delay in milliseconds (default: 1000) */
+  editorAutoSaveDelay?: number;
+
   // Terminal Configuration
   /** How to open terminals from "Open in Terminal" worktree action */
   openTerminalMode?: 'newTab' | 'split';